/**
 * Licensed to Open-Ones Group under one or more contributor license
 * agreements. See the NOTICE file distributed with this work
 * for additional information regarding copyright ownership.
 * Open-Ones Group licenses this file to you under the Apache License,
 * Version 2.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a
 * copy of the License at:
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package mks.webshop.dao;

import java.util.Properties;

import org.apache.log4j.Logger;

/**
 * This class manages dao implementer(s).
 * @author thach.le
 */
public class DaoManager {
    /** Logger. */
    static final Logger LOG = Logger.getLogger("DaoManager");

    /** Properties of configuration file 'app.properties'. */
    private static Properties confProps = new Properties();

    /** Instance of IMasterDao. */
    private static IMasterDao mstDaoImpl;

    /** Instance of ITransactionDao. */
    private static ITransactionDao trsDaoImpl;

    static {
        try {
            confProps.load(DaoManager.class.getResourceAsStream("/app.properties"));
        } catch (Exception ex) {
            LOG.error("Could not load configuration resource '/app.properties'.", ex);
        }

        // get class of DaoManager implementation.
        String mstDaoImplClassName = confProps.getProperty("MasterDaoImpl");
        String trsDaoImplClassName = confProps.getProperty("TransactionDaoImpl");
        Class mstDaoClass;
        Class trsDaoClass;
        try {
            // Create instance for master
            mstDaoClass = Class.forName(mstDaoImplClassName);
            mstDaoImpl = (IMasterDao) mstDaoClass.newInstance();

            trsDaoClass = Class.forName(trsDaoImplClassName);
            trsDaoImpl = (ITransactionDao) trsDaoClass.newInstance();
        } catch (Exception ex) {
            LOG.error("Could not create instance of dao implementer '" + mstDaoImplClassName + "'.", ex);
        }
    }

    /**
     * Get an implementer of Master Dao.
     * @return implementer of Master Dao
     */
    public static IMasterDao getMasterDaoInst() {
        return mstDaoImpl;
    }

    /**
     * Get an implementer of Transaction Dao.
     * @return implementer of Transaction Dao
     */
    public static ITransactionDao getTransactionDaoInst() {
        return trsDaoImpl;
    }
}